Qrindeb



June 19, 1928. 1,673,845

R. PRATER l GRINDER Filed July 9, 1927 2 Sheets-Sheet l I I I I I I l l l I I I I l I l I i June 19, 1928.

- R. PRATER GRINDER Filed July 9l 1927 Patented June 19, 1928.

PATENT oFFlcE.

RALPH PRATER, F OAK PAX, ILLINOIS.-

GRINDEB.

Application led July 9,

My invention relates particularly to grinders of the type adapted for reducing m'aterials of various kinds although not llmited to this use alone.

The main objects of the invention reside in the provision of a simple and effective feedingr means for a grinder which is well adapted to maintain a uniform feed, and which is preferablyconveniently and accurately adjustable to vary the rate of feed, all with a view toward increasing the efiicienc-y of the grinder by effecting a. uniform feed and providing the proper feed for various materialsy fed to the grinder.

With these objects inview my invention consists in certain features of novelty in the construction, combination, and arrangement of parts by which the said object and certain other objects hereinafter appearing are effected all as fully described with reference to the accompanyingdrawings and more particularly pointed out in the appended claims.

In the said drawings- Figure 1 is a side elevation of a grinder embodying my invention with parts broken away and in section;

Figure 2 is an enlarged partial section on the line 2-2 of Figure 1;

Figure 3' is a partial top plan view of the grinder;

Figure 4 is a partial end elevation of the same.

Like characters of reference indicate like parts in the several views.

Referring to the drawings 1 designates a grinder casing, and extending through this casing is a horizontally disposed revoluble grinder shaft 2. See Figure` 1. The casing 1 is provided with an end inlet opening 3 disposed in an upright plane above the shaft 2, and the casing is provided with a bottom discharge opening across which is' 'disposed a sizing screen 4. Blades or hammers 5 within the casing 1 and carried and rotated with the shaft 2 serve to reduce material fed into the casing until it is of such size that it discharges through the screen 4. Further description of this portion of the grinder is unnecessary for the present purposes, it being fully described and claimed in my copendin'g U. S. application for Letters Patent, Serial No. 175,997, filed March 17 ,-1927, for

im rovement in grinder.

ecured with the casing 1 and inclining 1927. smal No. :mana

casing is a feed hopper 6 which is provided with a bottom opening 7 ad'acent said inlet opening. A plate 8 is disposed in said opening 7 and continues the bottom of the hopper, and is pivotally mounted at its inner end on the hopper for vertical movement With respect thereto, as designated at 9. A flat spring 11 is secured on the hopper 6 underneath the same and inwardly beyond the inner end of the plate 8, as designated at 12, and is engaged with a block 13 secured to the plate 8 underneathl the same for yieldably urging the plate 8 downwardly. An eccentric 14 is secured on the shaft 2 underneath the block 13, and the lblock -13 engages downwardly upon the eccentric 14, so that as the shaft 2 rotates the eccentric 14 and the spring 11 effect a vertical vibration of the plate 8 for the feeding of material in the hopper into the casing 1 through the inlet opening?, of the casing.

A vertically disposed and vertically movable plate 15 is disposed against the vertical outer surface of the inlet opening end wall of the casing 1, and the lower edge of this plate forms the upper edge of the inlet opening '3, so that this inlet opening may-be varied to vary the rate of feed of material into the casing 1. The late 15 is secured in vertically adjusted position in the following manner. See Figures 1 and 4. A screw 16 is passed outwardly through and is se-`- cured in a bore through the inlet opening end wall of the casing 1 and is disposed above the inlet opening 3 in central relation therewith. The screw 16 passes through a vertical slot 17 in the plate 15, and a thumb nut 18 engaged on the outer end of the screw 16 serves to clamp the plate 15 against the casing 1 to secure this plate in vertically adjusted position, the slot 17 permitting vertical adjustment of this plate.

Engaged on the screw 16 between the plate 15 and the nut 18 is a washer 19 which is secured against rotation on the screw 16 in a usual manner, and this washer is provided with diametrically opposite horizontally disposed pointers 20 which cooperate with scales 21 on the plate 15 for redeterminately adjusting this plate. ee Figures l and 4.

In operation material in the hopper 6 passes over the plate 8, and rotation of the grinder shaft 2 eects vertical vibration of the plate 8 with the result that a uniform feed of the material into the grinder is effecte'd, the rate of which feed may be varied by the adjustment of the plate l5. The arrangement'I of. the plate 8 adjacent the inlet opening of the grinder is particularly advantageous in that it prevents the clogging of material at the inlet. opening because lt vibrates the material against the upper edge of the inlet opening and thus works it through the inlet opening, with the result that material consisting of large pieces, such as corn cobs, arev passed into the grinder at a uniform rate. t

While I have herein shown and particularly described the preferred embodiment of my invention I do not wish to be limited to the precise details of construction shown as changes may readily be made without departing from the spirit of my invention, but having thus described my invention I claim as new and desire to secure by Letters Patent the following:- e

1. In a grinder the combination with a hopper inclined downwardly toward its discharge end and provided with a )bottom opening adjacent its discharge end, `of a late disposed in said opening and continulng the bottom of the hopper and pivotally mounted at its inner end for vertical movement with respect thereto, spring means yieldably urgin vsaid plate in one direction, and means for intermittently o erating the ,plate in the opposite direction or'effecting vibration thereof for the feeding of material in said hopper. v

2. In a grinder the combination with a grinder caslng provided with an inlet openmg' and a grinder shaft disposedbelow said opening, of a hopper inclined downwardly to said opening, a vertically movable member adjacent said inlet opening and having an upwardly facing surface disposed correspondingly with the bottom of the hopper and over which material in the hopper passes, and means for vertically vibrating said movable member including a revoluble member below said hopper and fast on said shaft.

with respect thereto, an eccentric fast on said shaft below said plate, a block secured to said plate underneath the sanne'and engaging downwardlyon said eccentric, and a ilat spring secured with said hopper inwardly beyond the inner end of said late and engaged with said block for yiel ably urging said block and plate downwardly.

4. In a grinder the combination with'a grinder casing provided' with an end inlet opening disposed in an upright plane and a grinder shaft extending longitudinally of said casing and disposed below said opening, of a hopper inclined downwardly to said op'ening and provided with a bottom opening adjacent said inlet opening, a plate disposed in said opening of the hopper and continuing the bottom thereof and pivotally mounted at its inner endl on the hopper for vertical movement. with respect thereto, an eccentric fast on said shaft below said late, a block secured to said plate underneat the same and engaging downwardly on said eccentric, a fiat spring secured with said hopper inwardly beyond the inner end of sald plate and engaged with said block for yieldably urging said block and plate downwardly, a second plate disposed upright and. vertically movable and forming the upper edge of said inlet opening, `and meanscarried by said casing for adjustably positioning said plate in its said vertical movement'.

In witness whereof I hereunto ailix my signature this 5th day of July, 1927.

RALPH PRATER. 

